Apparatus for separating two sheets



1967 w. LIMBERGER APPARATUS FOR SEPARATING TWO SHEETS Filed Oct. 25, 1964 United States Patent 3,304,081 APPARATUS FOR SEPARATING TWO SHEETS Walter Limberger, Hamburg-Poppenbuttel, Germany, assiguor to Lumoprint Zindler K.G., Hamburg, Germany Filed Oct. 23, 1964, Ser. No. 406,031 Claims priority, application Germany, Oct. 30, 1963, L 46,214 Claims. (Cl. 27118) The invention relates to a device for separating two sheets, advanced in the forwarding direction by a conveyor with their leading edges oflset relative to one another, and comprising a pivotal body with conveying members which grip the leading edge of one sheet and cause through the exerted tension a rotational moment of the said pivotal body.

The invention also relates to an apparatus for producing copies by means of the so-called transfer method, comprising a pair of squeeze and/or transport rollers at the outlet of a developing device and with a separating device downstream thereof.

The present invention is based particularly on a separating device such as described in German Patent No. 965,- 839.

The operating speed of the known device, and especially of the devices upstream thereof, as viewed in the direction of the material flow, is limited, since during the separation impact-like effects on the sheets to be separated are to be avoided.

This is also essential, because the invention is not restricted to the application of a diffusion method in which the sheets are held in relatively tight superposition by sticking together in the moist condition. Thus, for example, in the so-called powder picture transfer in electrophotographic methods, a sheet to be discharged must be deflected without sudden shock and must be pulled off without exerting any substantial force in the direction of the contact face between the two sheets, so as not to destroy the transferred powder picture which is, at this stage, still movable.

The present invention may also be used with other transfer methods, e.g., with thermal transfer methods.

The invention has therefore the object of providing a separating device which deflects the edge of an advancing sheet without exerting a pressure effort thereon and pulls off the sheet following this edge, without thereby exerting a substantial pull on the said sheet in the direction of the contact face between two sheets.

According to the invention, this object is realised in that the pivotal body has a guide member deflecting the advancing sheet towards the conveying means, wherein the said guide member is moved out of the conveyor path by pivoting the pivotal body. By means of this deflecting member, the advancing sheet is deflected or reversed as known in the art without any relative movements. The deflection may be effected with a small or with a large radius of curvature, because after the completion of the deflection the deflecting member is moved out of the path of the conveyor and a part of the deflecting curvature may be within the said conveyor path even in the engaged position of the deflecting guide member.

By providing the said pivotal body with resilient means, these resilient means retain resiliently the guide member in a position blocking the conveyor path, and the conveying means in a position remote from the conveyor path. This effect is directly opposite to the action of the resilient means disclosed in the above-mentioned patent.

In a preferred embodiment of the invention, the said pivotal body is divided into two pivotably articulated sections, of which one contains the conveying means and ice the other forms the guide member. Both sections are connected by a linkage. In this manner it is possible to obtain mass distributions and positions, wherein the movements of the pivotal body or of its sections can be produced with minimum forces and practically without inertia.

It is an essential feature of the invention that the linkage is so arranged and designed with regard to the pivot bearings and the effective ends of the said sections that these sections are associated with different lever arms so as to move the effective end of the guide member through a longer path than the effective end of the section containing the conveying means. This is important so that even with a slow initial movement of the conveying means, having the larger mass, the deflecting member is quickly lifted out of the conveyor path. If the conveying means tend to produce a larger pull, i.e., a higher drive velocity than that caused by the conveyor, the small required effort and the arrangement of the path of movement make it possible to arrive at such an arrangement that the difference in the transport velocity between the conveyor on the one hand and the conveying means on the other hand is taken up by the pivoting movement of the conveying means, having regard to the length of the sheets to be separated, wherein the deflecting element is moved during its initial pivotal movement sufficiently out of the conveyor path to enable the following sheet to run on straight through the conveyor.

According to a further preferred embodiment, the conveying means comprise, as known in the art, a driven pair of transport rollers, and preferably a slipping transmission between the driving motor and the rollers. This slipping transmission may be set in such a way that it is comparatively soft, and the type of transmission will be chosen in accordance with the method and with the cohesive force between the sheets, for which the device is being used.

According to the above, the device according to the invention makes the same suitable for applications with which a separating could not hitherto be provided.

In view of the matching with the transfer method used, the present invention relates also to an apparatus for producing copies by means of transfer methods, and more particularly chemical transfer methods, conveniently diffusion methods, wherein softened and mutually reacting layers are pressed together. In these cases it is necessary for the sheets to remain in contact for a certain time after they have been pressed together. Thus, e.g., there is no copying device using the silver salt diffusion method available on the market today which comprises a separating device downstream of the delivery slot for automatically separating the papers (insofar as sheets are used). The difficulties encountered in this case are due on the one hand to the cohesive forces and on the other hand to the period of time required for the post-diffusion after passage through the .squeeze rollers.

In view of the advantages hereinbefore mentioned makes possible a device for producing copies, for example by means of the diffusion method, using a separating device which deflects the leading edge in a frictionless manner laterally through an opening of a guide member located downstream of the pair of squeeze and/or transport rollers. More particularly, a conveyor track defined by the guide members is located with a length downstream of the pair of squeeze and/ or transport rollers, permitting, in view of the conditions of the method used, a post transfer prior to the separation, and a guide member is equipped with an opening behind which the transport means are pivotably retained, whilst the oppositely mounted guide member has an opening through which the deflecting guide member may be moved. A certain path v. is provided for the post diffusion, but this may only be realised if the sheet is not affected by any forces producing a relative movement and the sheet to be lifted is, in fact, lifted off without such relative movement.

According to yet another feature of the invention, there is downstream of the conveyor path a continuation of the said guide members, within the range of which there is arranged a pair of pull-off rollers, the conveying speed of which is synchronized with that of the squeeze and/or transport rollers. This is important in order to ensure that the passage through this latter continuation is equally uniform if, say, the trailing edge of the sheet has already left the conveyor track causing the deflecting guide member to tend under spring action to return to the closed position. The pull exerted by the pair of pull-off rollers ensures that the sheet to be thereby removed can withstand the contact pressure of the deflecting guide member. Preferably and conveniently, this continuation is curved towards the side remote from the conveying means and a source of heat is arranged on the outside of this curvature.

Owing to this curved configuration, the coated side cannot rub against the guide members whilst it is simultaneously affected by the heating source. Conveniently, at least one guide member of the said continuation is perforated and a heat source is provided adjacent to this guide member.

According to a particularly preferred embodiment, in which the pair of squeeze and/or transport rollers is arranged substantially in a horizontal plane, the conveyor path extends substantially vertically and the pivotal body or its sections are arranged substantially vertically, and on either side of the conveyor path, there are arranged collecting tables for the delivered sheets of material. In

this arrangement, and especially by an extended construction of the sections in the form of two-armed pivoting levers, the sections may oscillate about an instable vertical position through a small angle so that only small adjusting forces occur owing to the small angular deflection.

The invention will be further described, by way of example, with reference to the accompanying drawing, showing a diagrammatical side elevation of a preferred embodiment of the invention with an apparatus for producing copies.

This arrangement comprises a housing with a section 1 and an outlet 2. The housing contains, upstream of the outlet orifice a pair of squeeze and/or transport rollers 3, 4, driven rotatively by a motor 43 in the direction of the arrows. For producing copies according to the diffusion method, the arrangement has upstream of the pair of squeeze and/ or transport rollers a developing tank with guide members through which two coated carriers, i.e. sheets, are supplied at least for a certain part of the path within the liquid along different tracks. The definite pressing together is affected by the squeeze and/ or transport rollers from which the coated carriers issue in a pressed together condition. It is a condition for the method according to the invention that one coated carrier, in the drawing the negative carrier indicated by the arrow 5 has its leading edge in front of the leading edge of the positive carrier 6. The developing and transfer takes place along a transport path, the end section of which is shown at 44. Downstream of the orifice 2 is a conveyor path 7, defined by the guide members 8, 9. The guide member 8, adjacent to the negative sheet, has an opening 10. The guide member 9 has over a substantial centre portion one or more slot-shaped openings, into which may engage one end 11 of a guide member 12, having a planar configuration in the case of a wide opening and a comb-shaped one with several slots. The ends of the said guide member 12 are bent at 13 at an angle of about 90 towards the guide member 8, the arrangement being such that in the position drawn in solid lines, the guide member protrudes with its bent end portion 14 into the opening or openings and the shaft of the section passes at 11 gradually through the conveyor path.

The guide member 12 has in this embodiment a pivot bearing 15 and is pivotably mounted in a frame, not shown on the housing 1. The said guide member 12 may be constructed as a two-armed lever with relation to this pivot bearing 15. The frame has delivery slots 41 and 42.

Adjacent to the guide member 8, there is a rodshaped section 16 of the pivotal body, consisting, for example, of two stays, and equipped with a pivot bearing 17 about which it is pivotable. Reference numeral 16 signifies the pivotal body mounted outside the conveyor path, and also this section is formed by a two-armed lever relative to the pivot bearing 17 the pivot 18 of which is located in the frame 40. The lever arm 19 equipped with the working end carries transport means formed by two drive rollers 20, 21, revolving as indicated in the drawing. A drive motor 22 is mounted preferably concentrically to the pivot 18 in the frame and carries a take-oft member 23, such as a disc also arranged concentrically to the pivot. The frame 40 may consist, for example, of two walls extending parallel tothe plane of the drawing, mounted in spaced relationship, and retaining the bearings and mounting for the parts arranged thereinbetween.

Between the take-off member 23 of the motor and a roller 21, there is a transmission 24 which may be extensible and permits a certain amount of slip. However, this transmission may have another known construction, such as a friction clutch or a slipping clutch of the kind which slips when a braking force is affecting the rollers 20, 21. The pair of rollers is rotatively driven in the direction indicated by the arrows.

The pair of rollers 20, 21 is so mounted in the frame 40 that the tangential plane of contactpasses through the opening 10. The section 16 is equipped with a spring 25 whose other end is arranged in the frame, say on the guide member 8, and has the effect of lifting the arm 19 with the pair of rollers 20, 21 from the opening 10.

The arm 26 of the section 16 remote from the working end with the roller pairs 20, 21, relative to the pivot bearing, is articulately connected by a linkage 27, mounted laterally outside the conveyor path, with the arm 28 of the guide member 12, remote from the working end. If the section 16 is pivoted in a clockwise direction, the guide member 12 is pivoted in the same sense about the pivot bearing 15. It may be seen that the pivot bearings 15 and 17 are arranged at different distances from the working ends of the section 16 and of the guide member 12, respectively so that also the arms remote from the housing 1 have different lengths. In this manner, when the section 16 is pivoted through a small amount, say, in the position 29 (broken line position) in which the conveying means move only through a fraction of the length of the arrow 30, the end 14 is pivoted through a much larger travel so that the end 14 is fully removed from the conveyor path already at the initial movement of the rollers 20, 21.

The operation of the arrangement is such that the sheets are advanced in the direct-ion of the arrows 5, 6 through the conveyor path 7, the leading edge of the negative carrier reaches the end 14 angled at 13 and is thereby guided to the pair of rollers 20, 21, and gripped thereby. .[he initially raised conveying speed produced by this pair of rollers, reacts on the section 16 to produce a torque, causing the section 16 to be pivoted in the position 29 whilst tensioning a spring 25. During the initial stage of the pivoting movement, the end 14. of the guide member 12 is lifted out of the conveyor path, permitting the positive carrier to proceed in a rectilinear direction. During the further movement, the section 16 may be pivoted further or may come to rest, according to the setting of the slipping clutch and of the pivotal range of this section 16. In the latter case, the force produced by the slipping transmission 24 causes both the section 16 and the guide member 12 to remain in the pivoted position. During this time, the positive sheet is advanced through the curved extension 31 of the conveyor path 7 and a pair of the delivery rollers 32, 33, revolving in the sense indicated by the arrows, and mounted in the frame 40. The drive may be derived from a motor 43. The action of this pair of rollers is synchronized with the feed velocity of the squeeze and/ or transport rollers 3, 4. It has the object of advancing the positive carrier sheet after the trailing edges of the sheets have left the pair of squeeze and/ or transport rollers 3, 4, and especially after the section 16 tends to return in the position shown, owing to the resilience of the negative carrier. At the same time, the guide element 12 has the tendency of returning into the position shown in the drawing. The pull exerted on the positive carrier retains this guide member in a sufficiently pivoted position on the reverse side of the positive carrier in order to permit its uninhibited passage. The curvature of the extension 31 ensures that inadmissible frictional effects on the coated side of the positive carrier are avoided.

In addition, its stiffness, and in many preferred applications also the adhesion on the negative carrier, ensure that the reverse movement does not occur before the trailing edge of the negative carrier has left the positive carrier. The said extension may consist, for example, of guide member sections 34, 35, of which at least the latter is profiled, for example, made up from webs mounted in the frame 40. On the outside of this guide member 35, there is mounted in a screen 36 within the frame 40 and within a reflector, a heat source 37, such as an infrared radiator.

' Naturally, this heat source is energized conveniently as a function of the pivoting movement of the said guide member 12.

In the indicated preferred embodiment with a substantially vertical arrangement above the delivery slot 2, in which the moving forces have been reduced to a minimum, because the deflections relative to the vertical are very small, there are provided on either side of the conveyor path 7 collecting tables or dishes 38, 39, for the positive and negative carriers. These tables or dishes are mounted by known means on the frame 40 which is equipped with two supporting walls extending parallel to the plane of the drawing. They are accessible through slots or openings 41, 42, in the frame 40.

Naturally, the arrangement according to the invention may also be extended horizontally, and more particularly, the extension 31 may be bent towards the side in which the transport means 20, 21, are located. Moreover, the extension 31 may be straight, and the heat source 37 may affect a zone in which the positive carrier is not deflected. This solution is particularly suitable for use with photoelectric devices, where the heat source has a raised intensity and acts as a bakingdn device effective after a powder transfer. In this case, the conveyor path 7 may be shorter. The housing 1 contains in this case an exposure device, as well as charging and powder application devices.

The invention shows spacially an apparatus for producing copies by means of the diffusion method at the scale of 1:1 or larger. This device with the conveyor path 7 and the frame 40 may be arranged particularly conveniently to form an attachment. It may be seen that the dimensions are small, while separate and dry copies may be produced by easy means. This advantage is novel and important, taking into consideration that ofiice personnel operating hitherto known office copying machines were compelled to hold the copy for some time before separating the sheets, and this delayed considerably the introduction of new materials for producing the next copy. Thus, the invention presents a novel feature, resulting in considerable saving in labour.

I claim:

1. A device for separating two sheets advanced by a conveying arrangement so that their leading edges are olfset relative to one another, comprising a conveyor path defined by a first and a second guide member, driving means arranged in the said conveyor path and adapted to move two superimposed sheets through the conveyor path, the said two sheets arranged with offset leading edges so that the leading edge of one sheet is in front of the leading edge of the other sheet, an opening arranged in one of the said guide members, namely in the guide member on the side of the conveyor path along which is advanced the sheet with the forward leading edge, a pivotal body arranged outside the conveyor path, adjacently thereto and on the side of the guide member with the opening, conveying means within the said pivotal body and arranged at a point outside the conveyor path and upstream of the said opening, said conveying means being positively driven and adapted to carry away a sheet of material applied thereto, a resilient support for the pivotal body in a position having a larger distance from the said opening than a sec-0nd position, a guide member protruding into the conveyor path and adapted to deflect the leading edge of a sheet through the said opening, a movable mounting for the said guide member adjacent to the conveyor path, connecting means between the said pivotal body and the guide member whereby the guide member is moved out of the conveyor path after the entry of the leading edge of a sheet of material.

2. A device as claimed in claim 1, wherein the said pivot-a1 body has an extended carrier on which the conveying means are mounted, a pivot bearing located on the said carrier so that the same is =pivota'ble about the pivot of the said pivot bearing, and wherein the said guide member is a pivoting lever and the conveyor path has a pivot axis about which the guide element is pivotable, and wherein the said guide member is arranged on the side of the conveyor path remote from the side having the pivotal body and the guide member has in addition to the guide element also an opening through which the end of the guide element is adapted to be moved.

3. A device as claimed in claim 2, comprising means actuating the unit comprising the pivotal body, the guide element and the connecting means and causing the said transport means to be resiliently retained in the position remote from the said opening and the guide element in a position passing through the said opening, while with a movement of the pivotal body in consequence of the entry of a sheet into the transport means the said guide element is lifted out of the conveyor path while tensioning the resilient means.

4. A device as claimed in claim 1, wherein the pivotal body and the guide element are formed by two-armed levers and each part has a pivot bearing in its centre range, wherein at the adjacent arms there are arranged the transport means on the pivotal body and a bent section on the guide element, said bent section passing in one position of. this guide element through the said opening, while the other arms of the pivotal body and of the guide element carry the connecting means and the resilient means actuate one of the other arms, and whereby the said pivotal body and the said guide element are arranged on different sides of the conveyor path.

5. A device as claimed in claim 2, wherein the lever arms of the carrier and of the guide element are so dimensioned that the one lever arm of the carrier carrying the transport means is shorter than the other lever arm of the carrier to which are articulately connected the said connecting means, whilst one lever arm of the said guide element, associated with the said opening, is longer than its other lever arm so that a comparatively small movement of the said transport means in a plane normal to the plane of the opening causes a larger movement of the lever arm of the guide element associated with the opening.

6. A device as claimed in claim 1, wherein the said transport means comprise a first and a second transport roller revolving one in tangential relationship with the other, and wherein there are provided driving means rotatively driving at least one of the said rollers.

7. A device for producing copies by means of a transfer method, comprising a frame, means forming a first conveyor path within the frame through which conveyor path are guided two laminar layer carriers in order to initiate a transfer process, a pair of squeeze rollers arranged in said frame at one end of the first conveyor path and between which rollers the superimposed layer carriers are carried in close contact, a driving arrangement for driving the said pair of squeeze rollers, a pair of guide members defining a second conveyor path downstream of the said pair of squeeze rollers, said guide members having such a length as to permit an image transfer between the laminar layer carriers after being pressed together by the said pair of squeeze rollers, means forming an opening in one of the said guide members at that end of the second conveyor path remote from the said squeeze rollers, and a deflecting member movable between a first position wherein an end portion thereof extends across the second conveyor path to deflect an edge of one of the advancing layer carriers through the said opening to a second position wherein it lies outside of the second conveyor path.

8. A device as claimed in claim 1, wherein the said conveyor path is extended by a further conveyor path, defined by third and fourth guide members, and wherein a pair of transport rollers adapted to serve as take-off rollers are disposed proximate to an end of said further conveyor path, said transport rollers being rotatably mounted in the said frame and revolving in peripheral contact with one another, at least one of these transport rollers being driven at a speed corresponding to the forwarding speed of the said driving means.

zontal plane, wherein the conveyor path with the first and second guide members is substantially vertically arranged, the pivotal body and its carrier and the guide element are retained substantially vertically, and on either side of the substantially vertical conveyor path there are arranged on the frame collecting tables for the delivered sheets of material. I

References Cited by the Examiner UNITED STATES PATENTS 3,017,179 1/1962 Stuckens 271-64 3,112,926 12/1963 Stuck ens 27164 3,143,948 8/1964 Hodges et a1 271-64 3,163,099 12/1964 Limberger 271-64 M. HENSON WOOD, JR., Primary Examiner.

A. N. KNOWLES, Assistant Examiner. 

7. A DEVICE FOR PRODUCING COPIES BY MEANS OF A TRANSFER METHOD, COMPRISING A FRAME, MEANS FORMING A FIRST CONVEYOR PATH WITHIN THE FRAME THROUGH WHICH CONVEYOR PATH ARE GUIDED TWO LAMINAR LAYER CARRIERS IN ORDER TO INITIATE A TRANSFER PROCESS, A PAIR OF SQUEEZE ROLLERS ARRANGED IN SAID FRAME AT ONE END OF THE FIRST CONVEYOR PATH AND BETWEEN WHICH ROLLERS THE SUPERIMPOSED LAYER CARRIERS ARE CARRIED IN CLOSE CONTACT, A DRIVING ARRANGEMENT FOR DRIVING THE SAID PAIR OF SQUEEZE ROLLERS, A PAIR OF GUIDE MEMBERS DEFINING A SECOND CONVEYOR PATH DOWNSTREAM OF THE SAID PAIR OF SQUEEZE ROLLERS, SAID GUIDE MEMBERS HAVING SUCH A LENGTH AS TO PERMIT AN IMAGE TRANSFER BETWEEN THE LAMINAR LAYER CARRIERS AFTER BEING PRESSED TOGETHER BY THE SAID PAIR OF SQUEEZE ROLLERS, MEANS FORMING AN OPENING IN ONE OF THE SAID GUIDE MEMBERS AT THAT END OF THE SECOND CONVEYOR PATH REMOTE FROM THE SAID SQUEEZE ROLLERS, AND A DEFLECTING MEMBER MOVABLE BETWEEN A FIRST POSITION WHEREIN AN END PORTION THEREOF EXTENDS ACROSS THE SECOND CONVEYOR PATH TO DEFLECT AN EDGE OF ONE OF THE ADVANCING LAYER CARRIERS THROUGH THE SAID OPENING TO A SECOND POSITION WHEREIN IT LIES OUTSIDE OF THE SECOND CONVEYOR PATH. 